From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [PATCH] Input: synaptics-rmi4 - Fix error handling in I2C transport driver Date: Sat, 1 Oct 2016 10:45:16 -0700 Message-ID: References: <1475109426-23644-1-git-send-email-linux@roeck-us.net> <20160929175540.GF7509@tuxbot> <20160930225403.GG30208@dtor-ws> <20160930230203.GH30208@dtor-ws> <74a818fc-6ebf-0514-461e-b664390c32cb@roeck-us.net> <1475342862.162608.742891553.456AA401@webmail.messagingengine.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from bh-25.webhostbox.net ([208.91.199.152]:36400 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751219AbcJARpT (ORCPT ); Sat, 1 Oct 2016 13:45:19 -0400 In-Reply-To: <1475342862.162608.742891553.456AA401@webmail.messagingengine.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Andrew Duggan , Dmitry Torokhov , Bjorn Andersson Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Duggan On 10/01/2016 10:27 AM, Andrew Duggan wrote: > > > On Fri, Sep 30, 2016, at 08:44 PM, Guenter Roeck wrote: >> On 09/30/2016 04:02 PM, Dmitry Torokhov wrote: >>> On Fri, Sep 30, 2016 at 03:54:03PM -0700, Dmitry Torokhov wrote: >>>> On Thu, Sep 29, 2016 at 10:55:40AM -0700, Bjorn Andersson wrote: >>>>> On Wed 28 Sep 17:37 PDT 2016, Guenter Roeck wrote: >>>>> >>>>>> Instantiating the rmi4 I2C transport driver without interrupts assigned >>>>>> (for example using manual i2c instantiation from the command line) >>>>>> caused the driver to fail to load, but it does not clean up its >>>>>> regulator or transport device registrations. Result is a crash at a later >>>>>> time, for example when rebooting the system. >>>>>> >>>>>> Fixes: 946c8432aab0 ("Input: synaptics-rmi4 - support regulator supplies") >>>>> >>>>> Sorry for that. >>>>> >>>>>> Fixes: fdf51604f104 ("Input: synaptics-rmi4 - add I2C transport driver") >>>>>> Cc: Bjorn Andersson >>>>> >>>>> Reviewed-by: Bjorn Andersson >>>> >>>> Applied, thank you. >>> >>> I take it back. rmi_i2c_init_irq() uses devm* so this whole thing mixes >>> up devm* and manual unregistering and unwind order is completely >>> broken. >>> >> Oops ... >> >>> 1. Why do we register interrupt from transport drivers and not make it >>> part of rmi_register_transport_device()? > > Not all RMI devices will have access to interrupts (ie HID and SMBus). > The same goes for regulators. Here is a reference to a previous > discussion regarding both: > https://lkml.org/lkml/2016/5/9/1055 > >> >> rmi_register_transport_device() doesn't take dev as parameter. >> >>> 2. If we need to use some non-devm-ised resources we should use >>> devm_add_action[_or_reset] to work these operations into devm stream. >> > > Since the regulator functions have their own devm_ versions I would > suggest switching to those functions to avoid dealing with > unregistering. > Maybe I am missing something, but I don't see a devm_regulator_bulk_enable(). devm_regulator_bulk_get() is already used. Guenter > Registering and unregistering the transport device is a bit more > complicated since these functions add and put the rmi_dev device. But, > it sounds like we can handle the unregister using > devm_add_action_or_reset(). >